night into thursday morning thick fog then. rain stays up around the northern sections of sonoma starting to tip towards san rafael by 5:00. as we head into the evening, drizzle will develop steadier rain will move into the bay at 10:00, through the heart of the bay while most of us are sleeping, waking up to the last vestiges of steady rain this south bay at 7:00, scattered showers through the morning, 1:00, 2:00, gone, cleaner, cooler air starts to move in fog wednesday night into thursday least amount of rain south bay. nearly 3/4 of an anyone's the north bay, greatest rain is going to fall in the higher elevations of sonoma county, up to two inches. sierra winter weather advisory above 7,000 feet, four to eight inches of new snow. south winds 50 miles per hour.